BOR event every 8 seconds

Hi PM_Dialog,

please have a look at the pdf attached. It is a section of our top layer gerber file.
There are 16 vias in the ground pad with one near the DCDC ground stub. Do you have any recommendations?

您能否确认GND PAD在芯片上连接在一起？

Hi PM_Dialog,

I’m still searching for the BOR issue and the support in this forum has not been helpful thus far. You are basically repeating what’s written in the hardware design guide.

To double check if it is a layout problem of my PCB, a colleague of mine designed a second PCB - the results are the same.

We also experimented with different stencil thicknesses and pad cutouts to make sure the GND pads are properly connected. The soldering process is noticeably better, but it did not solve the BOR problem.

Eventually I began to doubt that the BOR is due to poor grounding. So I dived in the source code. After hours of reading the data sheet, debugging and testing I found this code in hw_cpm_dcdc_config(void):

#if dg_configBLACK_ORCA_IC_REV == BLACK_ORCA_IC_REV_A
DCDC->DCDC_V14_0_REG &= ~(REG_MSK(DCDC, DCDC_V14_0_REG, DCDC_V14_CUR_LIM_MIN) |
REG_MSK (DCDC,以便决定C_V14_0_REG, DCDC_V14_FAST_RAMPING));

dcdc-> dcdc_v18_0_reg＆=〜（reg_msk（dcdc，dcdc_v18_0_reg，dcdc_v18_cur_lim_min）|
REG_MSK (DCDC,以便决定C_V18_0_REG, DCDC_V18_FAST_RAMPING));

dcdc-> dcdc_v18p_0_reg＆=〜（reg_msk（dcdc，dcdc_v18p_0_reg，dcdc_v18p_cur_lim_min）|
REG_MSK (DCDC,以便决定C_V18P_0_REG, DCDC_V18P_FAST_RAMPING));

dcdc-> dcdc_vdd_0_reg＆=〜（reg_msk（dcdc，dcdc_vdd_0_reg，dcdc_vdd_cur_lim_min）|
REG_MSK (DCDC,以便决定C_VDD_0_REG, DCDC_VDD_FAST_RAMPING));
＃其他
dcdc-> dcdc_v14_0_reg＆=〜reg_msk（dcdc，dcdc_v14_0_reg，dcdc_v14_fast_ramping）;

dcdc-> dcdc_v18_0_reg＆=〜reg_msk（dcdc，dcdc_v18_0_reg，dcdc_v18_fast_ramping）;

dcdc-> dcdc_v18p_0_reg＆= reg_msk（dcdc，dcdc_v18p_0_reg，dcdc_v18p_fast_ramping）;

DCDC->DCDC_VDD_0_REG &= ~REG_MSK(DCDC, DCDC_VDD_0_REG, DCDC_VDD_FAST_RAMPING);

reg = dcdc-> dcdc_ctrl_2_reg;
REG_SET_FIELD（DCDC，DCDC_CTRL_2_REG，DCDC_LSSUP_TRIM，REG，0）;
REG_SET_FIELD(DCDC, DCDC_CTRL_2_REG, DCDC_HSGND_TRIM, reg, 0);
dcdc-> dcdc_ctrl_2_reg = reg;
#endif

如果我编译在#else中写入的代码并将固件闪烁到DA14680，则不再发生BOR。
So I looked closer and narrowed the whole thing to 4 lines:

reg = dcdc-> dcdc_ctrl_2_reg;
REG_SET_FIELD（DCDC，DCDC_CTRL_2_REG，DCDC_LSSUP_TRIM，REG，0）;
REG_SET_FIELD(DCDC, DCDC_CTRL_2_REG, DCDC_HSGND_TRIM, reg, 0);
dcdc-> dcdc_ctrl_2_reg = reg;

These 4 lines prevent the microcontroller from restarting. What are these registry settings supposed do?

Hi point85,

在切换到4层设计后，我们摆脱了BOR。地层现在在顶层下面0.15毫米。在它是1.5毫米之前。